Girlfriend arrested: Diamond Reynolds, 27, the girlfriend of the late Philando Castile, was arrested in Minnesota on Thursday in connection to a hammer attack

The girlfriend of Philandro Castile who livestreamed his fatal shooting during a traffic stop in Minnesota last year has been arrested for allegedly assaulting another woman.

St. Paul police say they arrested Diamond Reynolds and two other women Thursday after a 24-year-old woman reported being attacked and struck in the head with a hammer Tuesday.

The victim sustained what has been described as serious injuries and was transported to Regions Hospital, where she later identified her attackers.

Chnika Blair, 28, and Dyamond Richardson, 25, have been booked into the Ramsey County jail in connection to the incident, which took place at around 10.30am on Tuesday on Jessamine Lane near Hazelwood Street in St Paul, reported Twin Cities Pioneer Press.

Reynolds’ role in the alleged assault wasn't given in the police report. Police spokesman Steve Linders says charges are pending.

Reynolds, 27, made headlines last summer when she used Facebook Live to broadcast the bloody aftermath of the fatal shooting of her boyfriend.

Castile, a 32-year-old black man, was shot by a police officer during a July 6 traffic stop in the St. Paul suburb of Falcon Heights.

Suspects: Chnika Blair, 28 (left), and Dyamond Richardson, 25 (right), have been named as suspects in Tuesday's incident in St Paul that left another woman injured

Prosecutors say the officer, Jeronimo Yanez, of the St. Anthony Police Department, a Latino, shot Castile seven times after the elementary school cafeteria worker told him he was armed. Authorities later discovered Castile had a permit to carry a weapon.

After the final shot, Reynolds frantically yelled: 'You just killed my boyfriend!'

Castile moaned and uttered his final words: 'I wasn't reaching for it.'

On Monday, Yanez pleaded not guilty to manslaughter and other charges. His trial is scheduled to begin May 30.

His attorneys say he had no choice but to shoot Castile after he saw a gun and perceived a threat to his life.

Prosecutors dispute whether the officer saw the gun.

Philando Castile (pictured), 32, was shot and killed by cop Jeronimo Yanez during a traffic stop in Falcon Heights, Minnesota, on July 6

Minnesota cop Jeronimo Yanez (left, in his mugshot, and right, in his police uniform) has pleaded not guilty over the shooting death a black man who was in a car with his girlfriend

Castile had a permit to carry the weapon. Audio recordings, NBC News reported last year, also revealed the cop pulled the car over because Castile and his girlfriend: 'just look like people that were involved in a robbery'.

Yanez's lawyers argued their client feared for his life and had no choice but to shoot Castile.

The shooting garnered headlines around the world because Diamond Reynolds livestreamed the moments after the shooting on Facebook.

There were widespread protests after the shooting as a result of the footage being broadcast.

The shooting's gruesome aftermath was streamed on Facebook by Castile's girlfriend, who was with him in the car along with her young daughter. At first the cop's gun could be seen being pointed through the window (left), before Castile was then covered in blood after being shot

Castile slumped to the side after he was shot (left), as his girlfriend, Diamond Reynolds, live streamed the moments after the shooting on Facebook

It was revealed for the first time what Castile's final words were moments before Reynolds started filming.

'I wasn't reaching for it,' Castile said seconds after he was hit with the bullets that would kill him.

Yanez was the first officer to have been charged in more than 150 police-involved deaths in Minnesota since 2000.

If convicted, he could face 10 years in prison and a $20,000 fine.

A memorial including a photo of Philando Castile adorns the gate to the governor's residence where protesters demonstrated after the shooting